PON1 and triple-A syndrome: Specifically, a study with 423 AAA patients and 423 matched controls found that the PON1 haplotype consisting of Leu55, Arg192, and Trp194 differed in frequency between control subjects (0.374) and AAA patients (0.288) (p < 0.042), suggesting a protective effect of this haplotype against AAA [48].